1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
#include <elf.h>
#include <limits.h>
#include <sys/mman.h>
#include <string.h>
#include <stddef.h>
#include "pthread_impl.h"
#include "libc.h"
#include "atomic.h"
#include "syscall.h"
int __init_tp(void *p)
{
pthread_t td = p;
td->self = td;
int r = __set_thread_area(TP_ADJ(p));
if (r < 0) return -1;
if (!r) libc.can_do_threads = 1;
td->detach_state = DT_JOINABLE;
td->tid = __syscall(SYS_set_tid_address, &td->detach_state);
td->locale = &libc.global_locale;
td->robust_list.head = &td->robust_list.head;
return 0;
}
static struct builtin_tls {
char c;
struct pthread pt;
void *space[16];
} builtin_tls[1];
#define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)
static struct tls_module main_tls;
void *__copy_tls(unsigned char *mem)
{
pthread_t td;
struct tls_module *p;
size_t i;
void **dtv;
#ifdef TLS_ABOVE_TP
dtv = (void **)(mem + libc.tls_size) - (libc.tls_cnt + 1);
mem += -((uintptr_t)mem + sizeof(struct pthread)) & (libc.tls_align-1);
td = (pthread_t)mem;
mem += sizeof(struct pthread);
for (i=1, p=libc.tls_head; p; i++, p=p->next) {
dtv[i] = mem + p->offset;
memcpy(dtv[i], p->image, p->len);
}
#else
dtv = (void **)mem;
mem += libc.tls_size - sizeof(struct pthread);
mem -= (uintptr_t)mem & (libc.tls_align-1);
td = (pthread_t)mem;
for (i=1, p=libc.tls_head; p; i++, p=p->next) {
dtv[i] = mem - p->offset;
memcpy(dtv[i], p->image, p->len);
}
#endif
dtv[0] = (void *)libc.tls_cnt;
td->dtv = td->dtv_copy = dtv;
return td;
}
#if ULONG_MAX == 0xffffffff
typedef Elf32_Phdr Phdr;
#else
typedef Elf64_Phdr Phdr;
#endif
extern weak hidden const size_t _DYNAMIC[];
static void static_init_tls(size_t *aux)
{
unsigned char *p;
size_t n;
Phdr *phdr, *tls_phdr=0;
size_t base = 0;
void *mem;
for (p=(void *)aux[AT_PHDR],n=aux[AT_PHNUM]; n; n--,p+=aux[AT_PHENT]) {
phdr = (void *)p;
if (phdr->p_type == PT_PHDR)
base = aux[AT_PHDR] - phdr->p_vaddr;
if (phdr->p_type == PT_DYNAMIC && _DYNAMIC)
base = (size_t)_DYNAMIC - phdr->p_vaddr;
if (phdr->p_type == PT_TLS)
tls_phdr = phdr;
}
if (tls_phdr) {
main_tls.image = (void *)(base + tls_phdr->p_vaddr);
main_tls.len = tls_phdr->p_filesz;
main_tls.size = tls_phdr->p_memsz;
main_tls.align = tls_phdr->p_align;
libc.tls_cnt = 1;
libc.tls_head = &main_tls;
}
main_tls.size += (-main_tls.size - (uintptr_t)main_tls.image)
& (main_tls.align-1);
#ifdef TLS_ABOVE_TP
main_tls.offset = GAP_ABOVE_TP;
main_tls.offset += -GAP_ABOVE_TP & (main_tls.align-1);
#else
main_tls.offset = main_tls.size;
#endif
if (main_tls.align < MIN_TLS_ALIGN) main_tls.align = MIN_TLS_ALIGN;
libc.tls_align = main_tls.align;
libc.tls_size = 2*sizeof(void *) + sizeof(struct pthread)
#ifdef TLS_ABOVE_TP
+ main_tls.offset
#endif
+ main_tls.size + main_tls.align
+ MIN_TLS_ALIGN-1 & -MIN_TLS_ALIGN;
if (libc.tls_size > sizeof builtin_tls) {
#ifndef SYS_mmap2
#define SYS_mmap2 SYS_mmap
#endif
mem = (void *)__syscall(
SYS_mmap2,
0, libc.tls_size, PROT_READ|PROT_WRITE,
MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
/* -4095...-1 cast to void * will crash on dereference anyway,
* so don't bloat the init code checking for error codes and
* explicitly calling a_crash(). */
} else {
mem = builtin_tls;
}
/* Failure to initialize thread pointer is always fatal. */
if (__init_tp(__copy_tls(mem)) < 0)
a_crash();
}
weak_alias(static_init_tls, __init_tls);
|
